CHARLESTON — West Virginia would slash property taxes in exchange for a new ‘‘cracker’’ plant and reserve funds to improve roads, schools and high-speed Internet access, under proposals Gov. Earl Ray Tomblin offered the Legislature in his State of the State address Wednesday.

The Logan County Democrat urged lawmakers to help the state compete with neighboring Marcellus producers Ohio and Pennsylvania for the 12,000 manufacturing jobs estimated to accompany such a petrochemical processing plant. He cited how the industry already has welcomed what it considers a clear set of rules for West Virginia Marcellus operations, approved in last month’s special session. The Marcellus shale field is considered among the world’s richest natural gas reserves.

Tomblin didn’t detail his plan to lawmakers for attracting the plant to West Virginia. But in an interview with The Associated Press, Tomblin said his proposal would shrink business property taxes for 25 years for any employer that invests at least $3 billion in a new plant. This highly sought facility would convert a byproduct from Marcellus shale natural gas wells — ethane — into a widely used chemical industry compound.

‘‘I will do everything in my power to make sure that West Virginia is positioned to take full advantage of this opportunity,’’ Tomblin told a House of Delegates chamber packed with legislators, other public officials and VIPs. ‘‘I will not limit our efforts to just one project or even two. We will compete for every project, every dollar of investment and every new job that relies on the natural resources with which we have been so blessed.’’

That’s already happening, Tomblin said.

He announced that drilling supplier Baker Hughes will create 275 jobs at a $40 million facility near the state’s active Marcellus field. That was among several economic bright spots that also include the Boy Scouts of America holding its 2013 national jamboree and scouting’s 2019 world jamboree at its new 10,600-acre reserve in southern West Virginia. The latter — the first time in 50 years that this gathering has been in the U.S. — should attract 80,000 scouts and their families, Tomblin added.

Tomblin also said West Virginia continues to weather the fragile recovery better than many states. Toward that end, Tomblin said he’s proposing no new taxes, and is sticking with scheduled gradual cuts to taxes on groceries, corporate net income and business equity. Such moves, he said, will save consumers and employers $84 million this year.

The new infrastructure fund he envisions would receive half of any tax revenue surplus as along as the state’s main emergency reserve equals at least 15 percent of general revenue spending. That ‘‘rainy day’’ fund is now at around 12 percent. Such a fund would have reaped an estimated $165 million from the previous budget year, if conditions were met, based on that year’s surplus.

‘‘We have to invest in ourselves if we expect others to invest in us,’’ Tomblin said.

House Minority Leader Tim Armstead, R-Kanawha, said afterward that the state should cut taxes instead of keeping such surpluses. While awaiting details on the economic proposals, Armstead welcomed Tomblin’s proposal to drug-test all enrollees in taxpayer-supported workforce training programs.

Expressing concern about substance abuse in the state, Tomblin asked lawmakers to pass that and to speed up the tracking of pain pill prescriptions. He also wants a state drug testing program for all coal miners.

Tomblin also invoked the Upper Big Branch disaster, which killed 29 underground miners in April 2010. He called for new standards for tamping down explosive coal dust, mandating sensors for detecting deadly methane gas and protecting whistleblowers. He also proposed beefing up pre-shift reviews of mine conditions and a one-year study of how miners, foremen and inspectors are trained.

Wednesday’s audience provided the first of six standing ovations during the 42-minute speech when Tomblin took aim at the mining-related policies of his fellow Democrat, President Barack Obama.

‘‘As long as I am governor I will continue to fight this administration’s war on coal!’’ Tomblin said.

A recent Tomblin-commissioned review of West Virginia’s education system, meanwhile, prompted the governor to propose annual reviews for teachers and making a new pilot project for handling teacher evaluations part of state law. Tomblin also asked lawmakers to struggling county school systems, including McDowell. Among the poorest places in the U.S., McDowell County has become the focus of a five-year rescue bid by a public-private partnership.

The leaders of West Virginia’s two main teachers’ groups afterward urged Tomblin not to rely too heavily on student test scores for evaluations. This process should improve teaching, not punish educators, they said.

During the 60-day legislative session that opened Wednesday, Tomblin said he will propose a crackdown on distracted driving by texting and hands-on cell phone use. He also wants to more quickly close a funding shortfall from non-pension benefits promised to public employees once they retire. Recent steps by state officials already have cut the estimated liability from these other post-employment benefits, or OPEB costs, in half to $5 billion.

Tomblin’s proposed budget for the fiscal year starting July 1 also will include $200,000 for two more mining inspectors, $10.7 million more for behavioral health services and $400,000 for a prison work camp for low-risk offenders. With inmate crowding at crisis levels, Tomblin also requested $5 million more for the state’s regional jails.

All told, the governor’s proposed budget would spend nearly $4.5 billion from general tax and lottery revenues. Public education would consume nearly half that amount. Medicaid and other social welfare programs account for another fifth. Higher education and public safety would each spend roughly 10 percent.

The proposal would increase such spending by $125 million over the ongoing budget, or nearly 3 percent. Much of that reflects rising health care costs, with the state’s share of Medicaid funding increasing by $80 million. It also provides much more detail about spending categories, after some GOP lawmakers had raised concerns last year about the size and number of ‘‘unclassified’’ budget lines.’’

Wednesday’s State of the State was Tomblin’s first since his close special election victory in October, which allows him to complete the term left by now-U.S. Sen. Joe Manchin. When Manchin resigned as chief executive in late 2010 to take his new post, Tomblin was Senate president and so began acting as governor under the state constitution’s succession provision. In that role, he presented a State of the State address in 2011.

Tomblin’s special guests Wednesday included Sgt. Benjamin Gentry III, among the first West Virginia soldiers to enter Iraq during the 2003 invasions, and the last state service member to leave that country, Sgt. James Providenti. Wednesday’s audience welcomed both them and Sgt. Robert Casas, a National Guard solider representing West Virginians who have served in Afghanistan. Representatives were also present for the West Virginia and Marshall university football teams, which each won bowl games this season.